312 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1921. 



So exuberant is the growth of vegetation in the humid tropics 

 that all spots from which the surface soil has been removed are 

 quickly covered with a new growth. Even steep railway cuts are 

 densely clothed with ferns, lycopodiums, begonias, and numerous 

 other plants, and a bare spot is to be seen only where there has been a 

 very recent landslide or where an overhanging bank has fallen. The 

 fences inclosing fields and plantations are living fences, made by 

 merely setting freshly cut poles or stakes into the ground ; even the 

 telephone and telegraph poles often break out in foliage, and trees 

 cut down inside a coffee plantation and taken outside had, as they 

 lay on the ground, taken root and thrown out new branches. 



As in parts of the Temperate Zone, there are in the Tropics many 

 local variations in the character of the forest. Some of these depar- 

 tures from the prevalent type are difficult to account for. Occa- 

 sionally one finds an area of forest on which the growth is con- 

 spicuously different from that of adjoining tracts. One such, on the 

 hills immediately above Bonilla 8 was as different in its appearance 

 and composition from other forests in that neighborhood as are 

 the post-oak and blackjack woods from the luxuriant mixed growth 

 of rich bottom lands in the middle or southern portions of the eastern 

 United States. There was little exuberance in either the under- 

 growth or the epiphytic and parasitic decorations upon the trees, 

 and but for the obvious fact that all the plants were different one 

 might easily imagine himself in an ordinary hardwood forest in the 

 States. 



On the Pacific slope, the country lying between the Central Cor- 

 dillera on the north and the Candelaria Mountains on the opposite 

 side of the San Jose Valley, as well as the mountains themselves 

 up to the cloud zone, and thence to the coast, has been completely 

 deforested, for it is there that the bulk of the population lives. Conse- 

 quently it is only on the higher parts of the mountains and in certain 

 places near the coast that any considerable part of the original forest 

 remains. Two trips, one on foot, the other on horseback, were made 

 through the virgin forest of the Pacific coastal plain occupying the 

 district about the lower course of the Rio Grande de Tarcoles, near 

 the Gulf of Nicoya, through which a cart road to Pigres had been 

 cut. There, two conspicuous features at once attract attention; the 

 rank undergrowth of canna-like plants (whether really cannas or 

 heliconias, I am unable to say), growing 10 to 12 feet high, which 

 covers the greater part of the ground, much as canebrakes do in por- 

 tions of our southern forests (pi. 5, fig. 2), intermingled with clumps 

 of small and beautiful but frightfully thorny palms, while most of 

 the large tree trunks were decorated for their entire length by a climb- 



8 The hacienda of Bonilla is on the Caribbean slope at an altitude of 2,600 feet. 



